The 31-year-old was driving on the Arnhem Highway southeast of Darwin when his car veered off the road about midnight on Monday.
Debris including side panels, a front bumper and the engine – strewn 100m along the road – was spotted by a passing motorist at 7am.
Batman was once married to fellow sprinter and Hockeyroo Nova Peris and the couple have two children together.
The Canberra-based athlete was in the Top End visiting his children after separating from their mother in 2010.
Northern Territory police detective Acting Senior Sergeant John Worrall said the crash occurred near the Adelaide River Bridge.
“Although we’re still in the early stages of the investigation, it appears as though the man was travelling east on the Arnhem Highway in a Holden Commodore when the vehicle left the road, crashed into a culvert and landed 10m off the road,” he said.
“At this stage it is believed speed and alcohol may have been contributing factors in the crash.”
Batman, a 100m, 200m and 400m sprinter, had competed at the 2000 Olympic Games in Sydney.
His best result on the international stage was a sixth place at the World Indoor Championships in 2003.
His 400m winning heat time of 46.11 remains the Australian indoor record. His time of 45.02 in Canberra in February 2003 is the eighth-fastest by an Australian.
Batman quit athletics in 2004 and turned his focus to rugby union and working as a real estate agent.
It is believed he was attempting a comeback this year in the hope of making the Olympic team for London.
Batman had studied at Scots College in Sydney and trained at the NSW Institute of Sport alongside Matt Shirvington, who last night said the news was “absolutely devastating”.
“It’s tragic news. He was a very talented athlete,” he said. “I believe he was the best all-round sprinter Australia has ever produced.”
Past and present members of the Australian athletics team also took to Twitter tonight to express their grief at Batman’s sudden death.
Hurdler Jana Pittman said: “So sad to hear the news of Daniel Batman’s passing. We spent most of our teens on trips together. Condolences to his family.”
Pole vaulter Steve Hooker added: “RIP Daniel Batman. You were truly an original. All our thoughts are with your young family.”
Sprinter Melissa Breen said Batman was taken too soon.
“RIP Daniel Batman. A life taken to young, our thoughts are with your family and close friends at this very sad time.”